FIG. 1 illustrates a prior art optical phased array 100 with a laser source 102 that delivers optical power to waveguides 104_1 through 104_N, which are connected to phase tuners 106_1 through 106_N. The optical output of the phase tuners 106_1 through 106_N is applied to corresponding optical emitters 108_1 through 108_N.
Optical phased array 100 implements beam shaping. By controlling the phase and/or amplitude of the emitters 108_1 through 108_N, the electro-magnetic field close to the emitters, known as the near field, can be controlled. Far away from the emitters 108_1 through 108_N, known as the far field, the electro-magnetic field can be modeled as a complex Fourier transform of the near field. To achieve a narrow beam in the far field, a flat phase profile in the near field is required. The width of the array determines the width of the far-field beam, scaling inversely. The slope of the near field phase profile determines the output angle of the beam. This means that by phase tuning the emitters, beam steering is achieved.
There is an ongoing need for improved optical phased array configurations, which is addressed with the embodiments disclosed herein.